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    Recent Progress of Triboelectric Nanogenerators for Biomedical Sensors: From Design to Application

    , Article Biosensors ; Volume 12, Issue 9 , 2022 ; 20796374 (ISSN) Rahimi Sardo, F ; Rayegani, A ; Matin Nazar, A ; Balaghiinaloo, M ; Saberian, M ; Mohsan, S. A. H ; Alsharif, M. H ; Cho, H. S ; Sharif University of Technology
    MDPI  2022
    Abstract
    Triboelectric nanogenerators (TENG) have gained prominence in recent years, and their structural design is crucial for improvement of energy harvesting performance and sensing. Wearable biosensors can receive information about human health without the need for external charging, with energy instead provided by collection and storage modules that can be integrated into the biosensors. However, the failure to design suitable components for sensing remains a significant challenge associated with biomedical sensors. Therefore, design of TENG structures based on the human body is a considerable challenge, as biomedical sensors, such as implantable and wearable self-powered sensors, have recently... 

    Design, preparation, and characterization of silk fibroin/carboxymethyl cellulose wound dressing for skin tissue regeneration applications

    , Article Polymer Engineering and Science ; Volume 62, Issue 9 , 2022 , Pages 2741-2749 ; 00323888 (ISSN) Farshi, P ; Salarian, R ; Rabiee, M ; Alizadeh, S ; Gholipourmalekabadi, M ; Ahmadi, S ; Rabiee, N ; Sharif University of Technology
    John Wiley and Sons Inc  2022
    Abstract
    Silk fibroin (SF) has been broadly applied in wound dressing fabrication because of its proper features for wound healing. In this work, we developed a carboxymethyl cellulose (CMC)/gelatin blend film with different concentrations of glycerol, and modified the optimized film with an SF layer through electrospinning process. Tensile strength and cell viability evaluation of blend films demonstrated that the glycerol content of 3% could be suitable as the substrate layer for the two-layer wound dressing. The morphology of the blend film and electrospun nanofibers was obtained from scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). It concluded that... 

    Thermal performance analysis of an energy pile with triple helix ground heat exchanger

    , Article Geothermics ; Volume 104 , 2022 ; 03756505 (ISSN) Farajollahi, A. H ; Asgari, B ; Rostami, M ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    A Ground Source Heat Pump (GSHP) is a renewable energy-based HVAC system that extracts or supplies heat from/to the ground via a Ground Heat Exchanger (GHE). One of the most commonly used types of GHE in GSHP systems is the energy pile. In this realm, the GSHP system with a triple helix energy pile has become the focus of attention. To this aim, a comprehensive three-dimensional transient Computational Fluid Dynamics model of the energy pile with triple helix GHE and the surrounding soil is developed. The effect of several parameters, including helix pitch, helix diameter and pipe diameter, on the thermal performance of the system, is investigated. Simulated cases are chosen using the design... 

    Chlorophyll-based wicking sensing bioplatform coupled with a smartphone-based sample-to-answer analytical device for on-site detection of picric acid

    , Article Biosensors and Bioelectronics: X ; Volume 11 , 2022 ; 25901370 (ISSN) Shafizadeh, M ; Abbasi Moayed, S ; Hamzei, Z ; Keshavarz, A ; Yousefi, S ; Hormozi Nezhad, M. R ; Golmohammadi, H ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    The development of inexpensive, equipment-free, portable, and user/environmentally-friendly analytical devices that can be efficiently utilized for on-site detection of PA is still a great challenge. To address these unmet demands, we have developed a smartphone-based disposable sensing bioplatform through immobilization of chlorophyll in a cotton thread for fluorescent monitoring of picric acid (PA). The fluorescence quenching of chlorophyll upon increasing the PA concentration based on the inner filter effect was considered as the sensing strategy in the developed sensor. The fabricated thread-based microfluidic sensing bioplatform was further coupled with a compact, low cost, portable,... 

    Photocatalytic degradation of vancomycin using titanium dioxide and optimization by central composite design

    , Article International Journal of Environmental Science and Technology ; Volume 19, Issue 9 , 2022 , Pages 8957-8968 ; 17351472 (ISSN) Dehghani, F ; Yousefinejad, S ; Dehghani, M ; Borghei, S. M ; Javid, A. H ; Sharif University of Technology
    Springer Science and Business Media Deutschland GmbH  2022
    Abstract
    Conventional wastewater treatment processes are not completely effective in removing vancomycin. In this study, affecting parameters on vancomycin degradation, such as pH, catalyst, initial vancomycin concentration, temperature, and reaction time were investigated simultaneously during a removal process based on titanium dioxide with ultraviolet irradiation in an aqueous solution. Titanium dioxide was synthesized and characterized using X-ray diffraction and scanning electron microscopy. The average size of the synthesized crystals was 4.7 (± 0.2) nm. Design of experiments was done by a central composite design based on the response surface methodology and multiple linear regression was... 

    Computational inverse design for cascaded systems of metasurface optics: comment

    , Article Optics Express ; Volume 30, Issue 20 , 2022 , Pages 36966-37005 ; 10944087 (ISSN) Zarei, S ; Khavasi, A ; Sharif University of Technology
    Optica Publishing Group (formerly OSA)  2022
    Abstract
    In a recently published article by Backer [Opt. Express 27(21), 30308 (2019).], a computational inverse design method is developed for designing optical systems composed of multiple metasurfaces. The forward propagation model used in this method was a discretized version of the angular spectrum propagator described by Goodman [Introduction to Fourier Optics, 1996]. However, slight modifications are necessary to increase the accuracy of this inverse design method. This comment examines the accuracy of the results obtained by the above-mentioned method by a full-wave electromagnetic solver and explains the reason of their difference. Thereafter, slight modifications to the method proposed by... 

    Details study on the kinematic characteristics of manta ray section in flapping motion and exploring its application in wave glider propulsion system

    , Article Sustainable Energy Technologies and Assessments ; Volume 53 , 2022 ; 22131388 (ISSN) Abbaspour, M ; Safari, H ; Darbandi, M ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    It has always been a human challenge to inspire natural configurations and phenomena and benefit from their merits in improving the performances of man-made proposed aero/hydro vehicles. For example, the manta rays are known for their great swimming performances. To design and fabricate an underwater robot based on the manta ray geometry and its kinematic characteristics, it is important to initially study its hydrodynamic behavior and possibly arrive at some key design parameters, which can remarkably help to figure out an optimum geometry with high swimming performances. The main objective of this study is to focus on the merits of gliding motion inspired by the manta ray fish considering... 

    A new scheme for the development of IMU-based activity recognition systems for telerehabilitation

    , Article Medical Engineering and Physics ; Volume 108 , 2022 ; 13504533 (ISSN) Nasrabadi, A. M ; Eslaminia, A. R ; Bakhshayesh, P. R ; Ejtehadi, M ; Alibiglou, L ; Behzadipour, S ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    Wearable human activity recognition systems (HAR) using inertial measurement units (IMU) play a key role in the development of smart rehabilitation systems. Training of a HAR system with patient data is costly, time-consuming, and difficult for the patients. This study proposes a new scheme for the optimal design of HARs with minimal involvement of the patients. It uses healthy subject data for optimal design for a set of activities used in the rehabilitation of PD1 patients. It maintains its performance for individual PD subjects using a single session data collection and an adaptation procedure. In the optimal design, several classifiers (i.e. NM, k-NN, MLP with RBF as a hidden layer, and... 

    Active learning of causal structures with deep reinforcement learning

    , Article Neural Networks ; Volume 154 , 2022 , Pages 22-30 ; 08936080 (ISSN) Amirinezhad, A ; Salehkaleybar, S ; Hashemi, M ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    We study the problem of experiment design to learn causal structures from interventional data. We consider an active learning setting in which the experimenter decides to intervene on one of the variables in the system in each step and uses the results of the intervention to recover further causal relationships among the variables. The goal is to fully identify the causal structures with minimum number of interventions. We present the first deep reinforcement learning based solution for the problem of experiment design. In the proposed method, we embed input graphs to vectors using a graph neural network and feed them to another neural network which outputs a variable for performing... 

    Development of consistent fish-bone simplified model with energy-based approach for efficient seismic evaluation of irregular steel moment resisting frames

    , Article Soil Dynamics and Earthquake Engineering ; Volume 161 , 2022 ; 02677261 (ISSN) Hosseini, M ; Ahmadie Amiri, H ; Esmailpur Estekanchi, H ; Kheirkhah Gildeh, M ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    This study aims to develop the Consistent Fish-Bone (CFB) simplified model for efficient estimation of Engineering Demand Parameters (EDPs) in irregular steel Moment Resisting Frames (steel-MRFs). To achieve this goal, some modifications based on the energy consistent approach have been applied to the Improved Fish-Bone (IFB) simplified model previously presented for reinforced concrete MRFs. These modifications include: 1) adding truss elements to the IFB model to consider the effect of flexural deformations and determining their areas by balancing the overturning moment and the strain energy due to the axial deformation of columns in the original steel-MRF with the overturning moment and... 

    Expectation-maximization algorithm to develop a normal distribution NHPP reliability growth model

    , Article Engineering Failure Analysis ; Volume 140 , 2022 ; 13506307 (ISSN) Nadjafi, M ; Gholami, P ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    One of the most important goals of any organization for a product that goes into the design or manufacturing process is to improve its reliability. Reliability growth is defined as improving a product's criteria (input parameters) during operation using changes in design or production. This paper presents a hardware-centric approach for the reliability growth of systems following normal distribution based on the Non-Homogeneous Poisson Process (NHPP). To reach this goal, the reliability growth modeling equations for the NHPP with the assumption of the normal distribution for failure data are extracted and obtained. Then, the maximum likelihood estimation technique based on the... 

    A new supply chain distribution network design for two classes of customers using transfer recurrent neural network

    , Article International Journal of System Assurance Engineering and Management ; Volume 13, Issue 5 , 2022 , Pages 2604-2618 ; 09756809 (ISSN) Najjartabar Bisheh, M ; Nasiri, G. R ; Esmaeili, E ; Davoudpour, H ; Chang, S. I ; Sharif University of Technology
    Springer  2022
    Abstract
    Supply chain management integrates planning and controlling of materials, information, and finances in a process which begins from suppliers and ends with customers. Optimal planning decisions made in such a distribution network usually include transportation, facilities location, and inventory. This study presents a new approach for considering customers’ differentiation in an integrated location-allocation and inventory control model using transfer recurrent neural network (RNN). In this study, a location and allocation problem is integrated with inventory control decisions considering two classes of strategic and non-strategic customers. For the first time, a novel transfer RNN is applied... 

    Cementitious mortars containing pozzolana under elevated temperatures

    , Article Structural Concrete ; Volume 23, Issue 5 , 2022 , Pages 3294-3312 ; 14644177 (ISSN) Toufigh, V ; Pachideh, G ; Sharif University of Technology
    John Wiley and Sons Inc  2022
    Abstract
    In recent years, pozzolana are being increasingly used in different types of concretes and mortars. This investigation aims to evaluate the effect of replacing 7, 14, 21, and 28% cement (by weight) with silica fume (SF), granulated blast furnace slag (GBFS), zeolite, and fly ash (FA) under elevated temperatures. Forty mix designs were built with various water-to-cement ratios and plasticizers. Three hundred and six specimens were prepared, and the flexural, uniaxial compression and tensile tests were performed on specimens after exposure to elevated temperatures between 25°C and 900°C. The X-ray diffraction (XRD) test was then performed on the two series of specimens. Accordingly, the... 

    Dynamics of electrostatic interaction and electrodiffusion in a charged thin film with nanoscale physicochemical heterogeneity: Implications for low-salinity waterflooding

    , Article Colloids and Surfaces A: Physicochemical and Engineering Aspects ; Volume 650 , 2022 ; 09277757 (ISSN) Pourakaberian, A ; Mahani, H ; Niasar, V ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    The slow kinetics of wettability alteration toward a more water-wetting state by low-salinity waterflooding (LSWF) in oil-brine-rock (OBR) systems is conjectured to be pertinent to the electrokinetic phenomena in the thin brine film. We hypothesize that the nanoscale physicochemical heterogeneities such as surface roughness and surface charge heterogeneity at the rock/brine interface control further the dynamics of electrodiffusion and electrostatic disjoining pressure (Πel), thus the time-scale and the magnitude of the low salinity effect (LSE). In this regard, film-scale computational fluid dynamics (CFD) simulations were performed. The coupled Poisson-Nernst-Planck (PNP) equations were... 

    Theoretical analysis of rotary hyperelastic variable thickness disk made of functionally graded materials

    , Article Structural Engineering and Mechanics ; Volume 45, Issue 1 , 2022 , Pages 39-49 ; 12254568 (ISSN) Soleimani, A ; Mahdavi Adeli, M ; Zamani, F ; Haghshenas Gorgani, H ; Sharif University of Technology
    Techno-Press  2022
    Abstract
    This research investigates a rotary disk with variable cross-section and incompressible hyperelastic material with functionally graded properties in large hyperelastic deformations. For this purpose, a power relation has been used to express the changes in cross-section and properties of hyperelastic material. So that (m) represents the changes in cross-section and (n) represents the manner of changes in material properties. The constants used for hyperelastic material have been obtained from experimental data. The obtained equations have been solved for different m, n, and (angular velocity) values, and the values of radial stresses, tangential stresses, and elongation have been compared.... 

    Toward visual chiral recognition of amino acids using a wide-range color tonality ratiometric nanoprobe

    , Article Analytica Chimica Acta ; Volume 1231 , 2022 ; 00032670 (ISSN) Jafar Nezhad Ivrigh, Z ; Fahimi Kashani, N ; Morad, R ; Jamshidi, Z ; Hormozi Nezhad, M. R ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    Chiral recognition has long been a challenging issue to deal with in biological systems, drug design and food authentication. Implementing nanoparticle-based probes with intrinsic or induced chirality in this field has addressed several issues concerning sensitivity, reliability, rapidness and the cost of chiral sensing platforms. Yet, research into chiral nanoprobes that can be used for visual monitoring of chiral substances is still in its infancy. As part of this study, a visual chiral recognition platform has been developed in which a combination of blue-emitting carbon dots (BCDs) and mercaptopropionic acid-capped CdTe quantum dots (MPA-QDs) with inherent chiroptical activity were... 

    Optimization of cervical cage and analysis of its base material: A finite element study

    , Article Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine ; Volume 236, Issue 11 , 2022 , Pages 1613-1625 ; 09544119 (ISSN) Jalilvand, E ; Abollfathi, N ; Khajehzhadeh, M ; Hassani Gangaraj, M ; Sharif University of Technology
    SAGE Publications Ltd  2022
    Abstract
    Nowadays, cervical disorders are common due to human lifestyles. Accordingly, the cage design should be optimized as an essential issue. For an optimal design, an objective function is utilized to calculate the proper geometrical parameters. Additionally, the base material of the cage plays a key role in its functionality and final cost. Novel materials are currently introduced with more compatibility with the bone in terms of mechanical and chemical properties. In this study, a cervical cage was modeled based on PEEK material with three types of tooth designs on its surface. The cervical cage is assumed to be implanted between C6 and C7 vertebrae. The geometric parameters of the cage were... 

    A review on computer-aided chemogenomics and drug repositioning for rational COVID-19 drug discovery

    , Article Chemical Biology and Drug Design ; Volume 100, Issue 5 , 2022 , Pages 699-721 ; 17470277 (ISSN) Maghsoudi, S ; Taghavi Shahraki, B ; Rameh, F ; Nazarabi, M ; Fatahi, Y ; Akhavan, O ; Rabiee, M ; Mostafavi, E ; Lima, E. C ; Saeb, M. R ; Rabiee, N ; Sharif University of Technology
    John Wiley and Sons Inc  2022
    Abstract
    Application of materials capable of energy harvesting to increase the efficiency and environmental adaptability is sometimes reflected in the ability of discovery of some traces in an environment―either experimentally or computationally―to enlarge practical application window. The emergence of computational methods, particularly computer-aided drug discovery (CADD), provides ample opportunities for the rapid discovery and development of unprecedented drugs. The expensive and time-consuming process of traditional drug discovery is no longer feasible, for nowadays the identification of potential drug candidates is much easier for therapeutic targets through elaborate in silico approaches,... 

    Development and verification of a flexible tethered satellite system model considering the fuel slosh

    , Article Multibody System Dynamics ; Volume 56, Issue 3 , 2022 , Pages 289-312 ; 13845640 (ISSN) Jafari Shahbazzadeh, Z ; Vatankhah, R ; Eghtesad, M ; Assadian, N ; Sharif University of Technology
    Springer Science and Business Media B.V  2022
    Abstract
    Removing space debris of various sizes, configurations, and properties from Earth’s orbits is one of the main missions of world space agencies. The existence of deactivated bodies within the path of other spacecraft increases the risk of collision. Althgough towing a satellite through a tether and taking it out of orbit may be a definite solution for space debris removal, most deactivated satellites have some fuel remaining in their fuel tank. This remaining liquid slosh within the tank directly affects satellite motion. To improve the mathematical modeling, the existence of unburned fuel is considered. More specifically, this research focuses on dynamic modeling and control of a selected... 

    Thermal study of the internal flow in a circular tube with vibrational ball turbulators

    , Article International Journal of Heat and Mass Transfer ; Volume 196 , 2022 ; 00179310 (ISSN) Saadat, M ; Aghlichanche, A ; Ataelahi, A ; Mohammadi, O ; Shafii, M. B ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    Flow turbulators have promising heat transfer applications. Here, the novel design proposed in our previous study (vibrational ball turbulators, VBTs, mounted on an elastic wire inside a circular tube) is investigated experimentally from heat transfer and thermal performance standpoints. The effects of diameter (Y) and longitudinal distance (pitch, X) ratios of VBTs, the Reynolds number, and the axial tension of the wire (σ0) on the average Nusselt number (Nu), the average Nusselt number ratio (Nu divided by that of a plain tube, Nup), the friction factor ratio (f/fp), and a parameter called the thermal performance factor (η=(Nu/Nup)/(f/fp)1/3) are studied. Different ball diameter (Y=0.3,...